Designing lead-free CaTiO3-based linear-like relaxor ferroelectrics with near-zero energy consumption

Constructing relaxor ferroelectrics (RFEs) in dielectrics is an efficient approach to break the so-called inverted relations between recoverable energy storage density ( W rec ) and efficiency ( η ). However, in view of the requirement for energy conservation, the major challenge of realizing near-zero energy consumption (ultrahigh η ) accompanied with high W rec still remains in the field of dielectric energy storage. Here, we designed a linear-like RFE with directly induced short-range local polar nanoregions via incorporating the ferroelectric into linear dielectric to realize high-performance capacitive storage, especially near-zero energy loss. Benefiting from linear-like RFE design, the combination of enhanced breakdown strength, ultrasmall dielectric loss, and minimized polarization hysteresis synergistically contributes to a record-high η of ∼97.7 % with a high W rec of 5.87 J/cm 3 and ultrahigh figure of merit of 255, which is ahead of most recently reported state-of-the-art lead-free ceramics. Moreover, based on such linear-like RFE merits, high thermal/frequency stability and cycling durability with high η > 90 % of the designed ceramics expand their applications in harsh condition energy storage systems. This study demonstrates the superiority of linear-like RFE design and provides a referential paradigm towards developing advanced near-zero energy loss energy storage dielectrics.